Modern assembly line manufacturing processes are typically highly automated to manipulate materials and devices and create a finished product. Quality control and maintenance processes often rely on human skill, knowledge and expertise for inspection of the manufactured product and manufacturing process.
Typical assembly line processes for processing wafers (e.g., semiconductor devices or materials) employ no specific inspection techniques at a robotic arm for calibration with a wafer carrying pod, also termed as a wafer pod, aside from manual inspections. Examples of wafer pods include standard mechanical interface (SMIF) pods which may hold a plurality of wafers, or front opening unified pods (FOUPs) which may hold larger wafers. Calibration may refer to a wafer being properly placed within a wafer pod at a wafer position. As an example, a wafer position may be a centered position that is away from any of the side, rear, or front walls (e.g., doors) of a wafer pod.
Calibration may be important as a robotic arm that is not calibrated with a wafer pod may place or retrieve wafers from the wafer pod in a manner that damages the wafer. For example, a non-calibrated robotic arm may damage a wafer by impacting the wafer carried by the non-aligned robotic arm against a side, front, or rear wall of the wafer pod. Conventional manual inspection and calibration techniques require large amounts of overhead and expensive hardware, but still fail to produce satisfactory results. Therefore, conventional inspection and calibration techniques are not entirely satisfactory.